Timetable application

Koleje Małopolskie operates dozens of bus and train routes across the entire Małopolska region, but their schedule data existed only in raw GTFS format, a technical standard passengers cannot directly interact with. The solution needed to be embedded inside their existing website without touching the host page, and had to support multi-modal connection search across hundreds of stops spanning two transport types.

We built a Flutter web widget with a bootstrap configuration system, so the client embeds the entire application by adding a single script tag and an empty container to their existing page. On the backend, a NestJS service handles nightly GTFS ingestion, checking for dataset changes via hash comparison and refreshing the database when updates are detected. The core of the connection search is a custom implementation of the RAPTOR algorithm, built from scratch based on the original Microsoft Research paper and extended to support multiple itineraries across mixed bus and train routes. A GraphQL API serves the frontend, background workers generate printable PDF schedules, and an admin panel lets the client configure route colours, highlighted stops and upload GTFS data manually when needed.